Lorenzo who, with teammate Valentino Rossi tested at Brno during the mid-season break went fastest on his first lap and would never be headed throughout the session. Behind the quickest lap time of 1'56.698, Pedrosa and Crutchlow were both three tenths off the lead pace and separated by just one hundredth of a second.
Despite a late fall for Bryan Staring on the CRT-specification GO&FUN Honda Gresini machine, it was a relatively quiet session in which the top five was rounded out by championship leader Marc Marquez (Repsol Honda Team) and the aforementioned Rossi, who won his very first 125 race at the Brno circuit in 1996.
In 22nd position was wildcard rider Martin Bauer, whose Remus Racing Team makes history by becoming the first ever Austrian outfit to compete in a premier class race of the World Championship. He ended the session ahead of three full-time riders.
Second MotoGP™ practice gets underway at 2:05pm local time (GMT +2).